Levich Institute Seminar Announcement, 11/15/2011
Tuesday, 11/15/2011
2:00 PM
Steinman Hall, Room #312
(Chemical Engineering Conference Room)

Professor Vanessa Ortiz
Columbia University
Department of Chemical Engineering

"A Molecular View of DNA Structure and Mechanics: Effects of Sequence on Bending and Hybridization"


ABSTRACT


The bendedness (kinks) and bendability (flexibility) of DNA are believed to play a major role in the affinity of certain sequences for histone binding. Theoretical and experimental attempts to observe and quantify bendedness and bendability have been hindered by an inability to directly resolve DNA structure and dynamics at the base-pair level. We have developed a model of DNA that includes previously unavailable features that are crucial for understanding bendedness and bendability at the molecular and microscopic length-scales. These include hybridization, sequence-dependent deformability and electrostatic effects. The model reveals that sequence does influence bendedness through the creation of kinks that arise when certain motifs slide past others to form non-native contacts. Bendability is also shown to be affected by sequence. These observations are shown to help explain the biologically observed preference of certain DNA sequences for histone binding.

BRIEF ACADEMIC/EMPLOYMENT HISTORY
  • PhD 2007 University of Pennsylvania, Philadelphia, PA Department of Chemical and Biomolecular Engineering
  • 2007-2010 University of Wisconsin-Madison, Madison, WI Department of Chemical and Biological Engineering
  • 2010-present Columbia University, New York, NY Assistant Professor in Chemical Engineering

RECENT RESEARCH INTERESTS:

My current research interests are in the study of the influence of molecular mechanics in molecular recognition in biological systems. The two applications of this subject that I'm currently focused on are molecular recognition in nucleosomes and in allostery.